Estimation of Macro and Micronutrients in Persimmon (Diospyros kaki L.) cv. ‘Rojo Brillante’ Leaves through Vis-NIR Reflectance Spectroscopy

The nutritional diagnosis of crops is carried out through costly elemental analyses different plant organs, particularly leaves, in the laboratory. However, visible and near-infrared (Vis-NIR) spectroscopy unprocessed samples has a high potential as faster, non-destructive, environmental-friendly alternative to analyses. In this work, technique estimate concentrations macronutrients such nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), micronutrients iron (Fe), manganese (Mn) boron (B), persimmon (Diospyros kaki L.) ‘Rojo Brillante’ been investigated. Throughout crop cycle variable rates N K were applied obtain six status levels trees an experimental orchard. Then, leaves systematically sampled throughout cropping season from spectral reflectance measurements acquired 430–1040 nm wavelength range. nutrients determined by inductively coupled plasma optical emission spectrometry (ICP-OES) for P, K, Ca, Mg, Fe, Mn B after microwave digestion, while Kjeldahl method was used N. partial least squares regression (PLS-R) model these leaves. calibrated using 75% remaining 25% left independent test set external validation. results indicated acceptable validation most nutrients, with determination coefficients (R2) 0.74 0.54 0.77 0.60 0.39 0.69 0.83 B. These findings support use Vis-NIR spectrometric techniques conventional laboratory methods although more research needed know how models developed one year perform ensuing years.